Question: Simplify the following expression: $k = \dfrac{1}{6a} + \dfrac{1}{5a}$
Answer: In order to add expressions, they must have a common denominator. The smallest common denominator is the least common multiple of $6a$ and $5a$ $\lcm(6a, 5a) = 30a$ $ k = \dfrac{5}{5} \cdot \dfrac{1}{6a} + \dfrac{6}{6} \cdot \dfrac{1}{5a} $ $k = \dfrac{5}{30a} + \dfrac{6}{30a}$ $k = \dfrac{5 +6}{30a}$ $k = \dfrac{11}{30a}$